There have been ink jet recording apparatuses that form an image on a recording medium by ejecting ink droplets from nozzles formed in an ink jet head.
In such an ink jet recording apparatus, nozzle clogging occurs due to air bubbles formed in the ink jet head or foreign matter or the like existing in the ink jet head, and a problem such as defective ejection is caused. Depending on the type of ink, the ink viscosity near the nozzles becomes higher due to ink particle sedimentation or the like, if the apparatus is left unused for a long time. As a result, it might become difficult to achieve stable ink ejection performance.
To counter this, there is a known ink jet recording apparatus that includes circulation flow paths that are provided in the head chip of the ink jet head and are capable of circulating ink, so that air bubbles and the like in the head can be made to flow, together with the ink, into the circulation flow paths.
For example, Patent Literature 1 discloses an ink jet head that includes: nozzles arranged in rows; a common supply flow path (a fluid inlet path) that supplies ink commonly to respective pressure chambers (pump chambers) that communicate with the respective nozzles; and a common circulation flow path (a recirculation channel) with which discrete circulation flow paths that discharge the ink near the respective nozzles communicate.